A Site Acceptance Test (SAT) is a structured set of checks performed on-site after installation and commissioning to confirm that an EV charging system works correctly in the real installation environment. SAT verifies that hardware, electrical integration, connectivity, safety functions, and backend operation meet the agreed requirements before the site is handed over for normal operation.
SAT is typically the final validation step after Factory Acceptance Testing (FAT) and before the site goes live with users.
Why SAT Matters in EV Charging Infrastructure
SAT reduces early-life failures and ensures the site is safe, compliant, and operationally ready.
– Confirms correct installation and wiring against design documents
– Validates protective functions and safe operation under real grid conditions
– Ensures chargers communicate reliably with the backend (often via OCPP)
– Prevents avoidable downtime, support tickets, and rework after go-live
– Provides documentation for handover, warranty start, and SLA activation
For public and fleet sites, SAT is also where operational rules (access control, tariffs, reporting) are confirmed.
What SAT Typically Covers
SAT scope varies by project, but commonly includes:
Electrical and safety checks
– Visual inspection: mounting, cable routing, labeling, ingress sealing, service clearances
– Verification of earthing and bonding (PE continuity, equipotential bonding where required)
– Protection verification: breaker ratings, RCD strategy, selectivity intent, correct settings
– Functional safety checks: emergency stop (if present), contactor behavior, fault responses
– Phase rotation / phase loss checks (three-phase sites), voltage limits, basic power quality sanity
Functional charging tests
– Start/stop sessions with intended methods (RFID, app, QR, payment terminal)
– Test charging on at least one compatible EV per connector type
– Verify delivered power levels and basic stability under load (11 kW / 22 kW / DC power)
– Verify session end behavior, connector release/locking, and user indications (LED/UI)
Connectivity and backend tests
– Network connectivity validation (Ethernet/LTE; SIM management status if cellular)
– OCPP connectivity, heartbeat, transaction flow, remote start/stop
– Firmware version check and any required configuration profiles
– Tariffs, authorization rules, and user groups (public vs staff vs fleet)
– Data correctness: meter values, session records, timestamps/timezone
Operational readiness
– Charger IDs, site mapping, and asset inventory confirmed
– Support contact info and escalation path documented
– Maintenance access and service clearances confirmed
– Evidence pack prepared (photos, checklists, as-built drawings)
How SAT Is Executed
SAT is usually performed using a formal checklist with pass/fail criteria.
– Pre-SAT review of as-built documentation and test plan
– On-site inspection and electrical verification by qualified personnel
– Live charging tests and backend confirmation
– Logging of defects (snag list) with severity and deadlines
– Retest of corrected items
– Final SAT sign-off and handover documentation
SAT results are often used to trigger warranty start dates and SLA measurement baselines.
Key Benefits of SAT
– Safer, more reliable site commissioning and handover
– Fewer post-launch failures and support calls
– Faster time to revenue for public sites and higher readiness for fleets
– Clear documentation trail for compliance, warranty, and dispute prevention
– Better coordination between installer, OEM, and operator responsibilities
Limitations to Consider
– SAT quality depends on having the right test equipment, EV test vehicle access, and backend readiness
– Some issues appear only under real traffic or extreme weather after go-live
– Connectivity variability can mask problems if tested in ideal conditions only
– Poorly defined acceptance criteria can lead to disputes between stakeholders
Related Glossary Terms
Factory acceptance test (FAT)
Commissioning
Installation scheduling
Charger commissioning
OCPP
Service level agreements (SLAs)
Maintenance access planning
Selectivity (discrimination)
Insulation resistance test
Charger availability KPIs